Oscar Pistorius of South Africa just qualified for the 400-meter and the 4x400-meter relay races at this year's World Championships, his first trip there. That's an amazing feat in itself, but made more amazing as Pistorius is a double amputee, using two carbon-fiber Cheetah prosthetic legs to run. He'll be the first-ever amputee athlete to perform at the event.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.